Exxon Production Research Company

William T Ilfrey

Richard H Gunderson

Joe K Heilhecker

James M Walker

Leo Donald Maus

William W Todd

William P Dixon

Thomas C Caldwell

Richard A Warriner

Philippe H Schaeffer

A marine riser system for use in deep water drilling operations from a floating vessel is disclosed. The riser system permits detachment of the lower end of the riser from the wellhead enabling the riser to be set aside to a position which is clear of the wellhead. Support means adjacent the wellhead can be used to support and position the riser when it is set aside. Tensioners, support mechanisms and guidance means are provided to move the riser back and forth between the wellhead and support means. In this manner, casing and tools having diameters larger than that of the riser can be inserted into the wellhead without returning the riser to the surface. Drilling operations with large diameter drill bits can also be conducted with the riser in the set aside position.

Riser set-aside system

A pressure energized seal to seal an annulus between two concentric cylindrical members, particularly well suited to be used as an annular casing seal in an oil and gas well. A circular sealing ring has both its upper and lower surfaces channeled to leave two upper sealing lips and two lower sealing lips which effect the seal by being forced against the sealing surfaces of the cylindrical members. Two circular setting rings can be used to spread the sealing lips into sealing engagement with the sealing surfaces of the cylindrical members. The setting rings would be partially disposed within the channels of the sealing ring and adapted to spread the sealing lips when the setting rings are moved toward the sealing ring.

Annular seal

Method and apparatus are disclosed for testing the pressure integrity of blowout preventers and wellhead casing hanger seals. An annular pressure chamber between the blowout preventer and wellhead casing hanger is formed by closing the blowout preventer on a tubular member having a test plug which seats within and sealingly engages the casing hanger. Pressure sensing means disposed along the length of the tubular member are used to monitor pressure above, below and within the annular chamber. Pressure changes detected by the sensing means are indicative of leakage across the blowout preventer or wellhead casing seal.

Casing seal and blowout preventer tester and test method

Apparatus and method for drilling a well into a submerged bottom from a floating drilling vessel while employing a riser pipe having positive buoyancy is disclosed. The riser pipe extends between the vessel and the well and is comprised of an upper and a lower section. Means are connected to the lower section for imparting a buoyant force to it of sufficient magnitude to render it positively buoyant. Means are provided extending between the submerged bottom and the upper end of the positively buoyant riser section for restraining the lower section against upward movement. The upper section of the riser pipe may be disconnected from the lower section so that the vessel may abandon the well site. The lower riser section is left self-standing, connected to the wellhead.

Self-supported drilling riser

An improved marine riser is described which is comprised of a plurality of conduit sections joined together end to end. Buoyancy cans for retaining a compressed gas are flexibly connected to the riser at selected locations along its length and form a fluid tight seal therewith.

Growing community of inventors

Houston, TX, United States of America

William T Ilfrey